The objective of the Genetics Core is to support research to better understand the role of genetic factors associated with normal and abnormal physical, cognitive and/or behavioral development. Supported research focuses on etiology, natural history and prognosis of a variety of conditions associated with developmental delay, neuropsychiatric disorders, and behavioral and physical features of developmental disabilities. These include phenotypic variations associated with genomic copy number changes, enzymatic deficiencies and new therapies, gene discovery, mutation analysis, genotype-phenotype correlation, and the role of copy number changes in morbidity. The services provided by the Genetics Core include: (1) cell line establishment and tissue culture, (2) cytogenetic analysis, namely karyotype and fluorescence in situ hybridization, (3) single nucleotide polymorphism microarray, and (4) identification of regions with genomic homozygosity and parent of origin for genomic abnormalities. The Core also serves as an interface for IDDRC-supported projects with the resources of the other Genetics Core facilities established within the Johns Hopkins Medical Institutions.